StringCoder

import java.util.ArrayList;

public class StringCoder {
private String masterString;
	
	public StringCoder (String master)
	{
		
		masterString = master;
	}
	
	public String decodeString (ArrayList<StringPart> parts)
	{
		String newStr = "";
		for (StringPart part : parts) {
			newStr = newStr + masterString.substring(part.getStart(), (part.getStart()+part.getLength()));
		
	}
		
					
		return newStr;
	}
	
	private StringPart findPart (String str)
	{
		
	    int count = 0, loc = 0;
		boolean found = false;
		String newStr;
		StringPart sPart = new StringPart();
		
		// pre-condition - all characters in String str will appear in the masterString
		
		while (found == false && count < str.length())   // second condition shouldn't be needed due to the pre-condition
		{
			newStr = str.substring(0,str.length()-count);
		    loc = masterString.indexOf(newStr);
		    if (loc == -1)
			{
				count++;
			}
			else
			{	
				sPart = new StringPart(loc, str.length() - count);		
				found = true;
			}
		}	
		return sPart;
	}
	
	public ArrayList<StringPart> encodeString (String word)
	{
		ArrayList<StringPart> sPartList = new ArrayList<StringPart>();
		String x = word;
		while (x.length()>0){
			StringPart y = findPart(x);
			sPartList.add(y);
			x = x.substring(y.getLength());
		}
		
		
		return sPartList;
		
	}
	
	
	
	

}